Hand rock-drill.



Patentedl June '17,. |902.`

'V.4 Y. SMITH.

HAND ROCKDRILL.

(Application led July 17, 1901..)

(No Model.)V

me Norms PVETERS C0. PHOTcrumo WASH UNITED STATESPATYENT.

. FFICE- vAL- ERIUs Y. SMITH, or OAKLAND, oALiroRniAg VHAND RooK-DR|L|..

sPEcIisIeArwIoNlforming'parecerse/ters Patent No. 702,499, cated .nine i?, 1902..'v Y f n Application led Julyv 17, i901. Serial No. 681635:. (No model.) I Y Y l To all-Z lteh/0mv tm/cry concern.-

Be it known that I, VALERIUS Y; SMITH, a

citizen 'of the United States, residing at Oakland,`county of Alameda, State of California, have invented an Improvement in HandRock- Drills; and vI herebydeclare the following to be a full, f clear, `and exact description of the same.

My invention relates to a device for drilling rocks and the like ,and a mechanism including an impelling-spring, means by which the drill is retracted against thel action of the spring, means' for releasing it andv allowing the spring to act, means for turning thedrill between each forward impulse, and a lever vand connected mechanism by the alternate movement ofV whichl the drill is retracted and released for each forward stroke.

My invention also comprises detailsof construction which will be'more fully explained .by reference to the accompanying drawings,

' in which- Figure 1 is a horizontal central section throughthe drill. Fig.- 2 is aside elevation of the same. Fig. 3 is a rear end view.

The drill :or cutting-bit'A is fixed by any f suitable'clamp, orfastening to a drill-shank 2, whichis slidableA within an outer easing 3 iiange at andy the collar 6.

of' any suitable or desired construction. The

forwardendof" the shank'is guided by the sides of the opening'through whieh'it passes at'the front ofv thel casing, as shown at 4. Near therear endit'passes through a guideopening formedv by 7 an lannular internal.

flange, as shownat. Upon the shank 2 within the-casing is'xed a\collar 6, which may be adjustable to anymd'esired point upon the shank. Between the collar and the annulighter spring 8 is fixed between the collar 6 andthe end of the casing, and this acts as a buffer to reduce the shock of the stroke, and

altering the'position'of the collarffi.y

opening inthe shankf2" and extending in-` wardly, so as to engage one` of ythe. spiral` 6o V grooves in the stein 9.

pon the outer le'nd of thestem 9 is a 'y ratchetwheel 11, and this is engaged by pawls 12, which are pivoted inchambers in a disk or head. 13, so that when the drill-shank 65 is retractedthe ratchet-wheel'1l,being held stationary by the pawls 142, the` spiral 9 being -engaged by the lug.10,will turn the drillshank slightly, andwhen released,sovthat the spring acts to drive it forward, the ratchet'7o will turn freely, not being held'by thepawls in that direction,l thus allowing the drill to strike the point of impact fairly. e y

In order to retract-the. drill land its shank,

I have shown a mechanism: consisting of ay 7.5

double lever centrally fulcrumed having rods extending from it V and l"carrying trip-levers which alternately engage a disk or'headlupon the drill-shank, so as to retract thelever, and' V are afterward disengaged'to'- allow the spring 8o c to impel itf'orward. Y,Thisfdouble centrallypivoted lever isshown at 14, andthe rods 15 are pivotedto the outer ends upon opposite sides ofthe'fulcrum-point. These .rods extend parallelwithl the 'casing and are slid- 85 able through holes in guides `16, suitably iked` at some point onthe casing. The trip-levers are fulerumedl inthe rods`15,*as shown' at 17, andv have arms 18 and 19, the firstV of which j projects through an open slot 20into'the eas- "9o ing,where it engages'a head 21, fixed upon t the rear end of the drill-shank.'` Theother j arm 19. extends rearwardly'and"approxiV mately parallel with the lineof movementof the carrying-rod l5, land this arm'is sobe'v- 95.` eled thatv in its rearwardf'movement 'itengages an incline 22, whichf'a'cts in retraction',

turning the two arms about the pivot-point 17 until the arm 18 is disengaged fromr the` v head 21. This occurs when the kdrill audits roo it may be made of any degree 0f stiffness by shank have been retracted to the full extent Y to engage and retract the latter, means in the ot the stroke rearwardly, and as soon as the arm 1S is thus disengaged the spring 7 is free to act and impel the drill forward. Aspring 28, pressing on the back of the arm 19, returns it to its normal position as soon as the rod 15 has been moved forward, so as to disengage the arm 1S) from the incline 22. In order to operate this device, I have shown a hand-lever 24E clamped to the hub of the double lever 14, so that by alternately moving the hand-lever up and down the double lever 14.- will be oscillated upon its fulcrum and will thus alternately push the rods 15 (one of which is connected with each end) backwardly, and, as before described, each of the arms 1S will alternately engage the head 21 and retract the drill. When the lever-arm is being moved su iiiciently to disengage the arm 18 by reason of the movement of the arm 19 over the incline 22, the opposite' arm will be advanced toits first position toward the front and will thus be out ot the way o't the head 21 when the drillis released, so that the spring acts upon it. The opposite movement of the lever 24C will then act to engage this last-mentioned arm 18 with the head 21 and retract it, while the other one is correspondingly moved forward. Thus by means of this oscillating lever 24; each complete oscillation of the lever gives two reciprocations of the drill and a correspondingly rapid advance.

Having thus described my invention, what I claim, and desire to secure by Letters Iatent, is-

1. The combination. in a drill of a slotted casing, a drill-shank guided and longitudinally slidable within the casing, means by which the drill and shank are partially rotated at each reciprocation, a double centrally-pivoted lever, slide-bars connected to the arms of said levers, spring-pressed bellerank levers pivoted in the rear ends of the slide-bars having one arm extending in the direction of the length of said bars and the other arm projecting laterally through the slot in the casing and into the path or" the drill-shank, to engage and retract the latter, and means for alternately engaging one ofthe arms of a bell-crank lever to withdraw the other arm from engagement with the drillshank.

2. The combination in a drill of a casing, a drillshank guided longitudinally therein, means by which the shank is given a partial rotation during each reciprocation, a centrally-pivoted lever on the outside of the casing, two slide-bars extending in the same direction and one' disposed over the other said bars each having one end connected to one arm of the centrally-pivoted lever, bell-crank levers pivoted in the rear ends of the slidebars, having one arm extending in the direction of the length of said rods and the other member projecting laterallyinto the casing in the path of the drill-shank, and adapted path of the first-named members of the bellcrank levers adapted to engage said members and alternately withdraw the other members from engagement with the drill-shank, and a spring by which the shank'is impelled forward after the release.

3. The combination in a drill of a casing, a spring-impelled drill-shank, means for partially rotating the same at each reciprocation, said shank having a head fixed to the rear end, and said casing having an opening in its side leading to said head, a double centrally-fulcrumed lever exterior to the casing, slide-bars disposed one above the other and both extending in the 'same direction, and having their front ends connected to the double lever, bell-crank pawl-levers mounted in the rear ends of the slide-bars, each having one arm extending in the direction ot the length of the bars and another arm eX- tending transversely and entering through the slot of the casing, and adapted to engage the head on the drill-shank, springs acting against said paWl-levers, and means in the path ot the levers for depressing them to cause the release of the retracted drill-shank.

4. The combination in a drill of a closed casing having an internal abutment, a centrallyguided slidable drill-carrying shank havinga head upon its inner end, and a spring surrounding the shank and having one end to seat against said abutment, said spring being compressible by the retraction ot' the drill-shank and acting to impel the latter forward when released bell-cranks carried by rods longitudinally slidable upon opposite sides of the cylinder, one arm ot' each bell-crank extending in the direction of the length of the rods and another arm extending transverse and entering an opening in the casing, and adapted to alternately engage the head of the drill-shank; fixed inclines on the outside of the casin g in the path of travel of the other arms of the bell-cranks, acting to disengage the first-named arms from the head of the drill-shank, and springs acting against the bell-cranks to return them to normal position after being depressed by the inclines; a double centrally-fulcrumed lever with opposite ends of which the rods carrying the bell-cranks are connected, and a single hand-lever connected with the center of the double lever, by the up-and-down movement of which said lever is oscillated.

5. The combination in a drill, of a closed cylindrical casing having a front guide for the drill-shank, a centrally-guided slidable drill-carrying shank having a head upon its inner end, spring-pressed bell-crank levers fulcrumed in the rear en d of the longitudinally-movable rods, one arm of each lever engaging the head on the drill-shank at each rearward movement, fixed inclines with which the other arms of the bell-cranks engage to release the drill-shank at the termination 0f its rearward movement, a fixed stop in the said collar capable of reguiatin'g the tension casing in front of said head and forming a of both springs, substantially asfdescrb'ed.' -Iov rear*l guide for the drill-shank, a collar and i In witness whereof I havehereunto set'm'yv means-forv changing its lposition upon the hand. drill-shank, a spring interposed and eom- VALERIUS Ylil-SMITH. pressible between the two when 'thedrill is. Witnesses: retracted, anda cushion-spring located be-l SgHQNOURSE,

tween the collar and the frontof the casing, H. F. ASCHECK. 

